Both theory and research suggest that the desire to regulate one's affective experience is an important motive underlying problem alcohol use. Both positive and negative affect are commonly cited reasons for alcohol use and relapse to use following treatment among individuals with an alcohol use disorder (AUD). Although the use of alcohol to regulate affective states may be viewed by the individual as adaptive in the short term, in the long term, drinking to regulate affect can prove to result in a host of negative personal, social and physiological outcomes. However, despite the strong links between affect and drinking, few studies have directly addressed whether interventions that target negative affect positively impact drinking outcomes among men and women with an AUD. In a completed Stage 1a/1b Behavioral Therapies Development study (AA016054), our research team successfully developed (Stage 1a) and conducted an initial evaluation (Stage 1b) of Affect Regulation Training (ART), a 12-session treatment supplement which was combined with standard cognitive-behavioral therapy (CBT) for alcohol use disorders to enhance alcohol treatment outcomes. To our knowledge, this is the first affect regulation intervention specifically developed for use with substance use disorders. This new treatment (ART) was then compared to a Health and Lifestyles control condition (HLS) that was combined with the same CBT for alcohol use disorders. Thus, both the ART and HLS conditions contained the identical CBT for alcohol use disorders component. This design provided a strong initial test of ART's efficacy because ART had to show a treatment benefit beyond that provided by an active, empirically-supported treatment for AUD (i.e., the CBT component of HLS). Study results provided promising empirical support for further developing ART as an enhancement to CBT treatment. Specifically, the study met all of the aims of the Stage 1b pilot study as outlined by Rounsaville et al. (2001): (a) excellent patient acceptance of ART (i.e., treatment retention and satisfaction, strong therapeutic alliance), (b) ability to recruit the target population, (c) feasibility of treament delivery with Master's level therapists in an outpatient setting, (d) clinically significant patien improvement in at least one important outcome domain (i.e., alcohol outcomes), and (e) effect size estimates to be used to determine the sample size for a Stage II clinical trial. For non-drinking outcomes, the results revealed small to moderate effects for several treatment process variables consistent with ART's proposed mechanisms of change (i.e., decreased negative affect, increased mindfulness, increased reappraisal, and increased emotion regulation skills). Given these promising results, we propose to conduct a fully-powered Stage II efficacy trial in which we will compare 12 weekly, individual sessions of ART to the HLS control condition. An important aspect of a Stage II randomized clinical trial is to determine how treatments exert their positive effects. Thus, the proposed study will explore several mechanisms of action by which ART is hypothesized to exert its positive effects on alcohol treatment outcomes. PROJECT NARRITIVE: Despite the strong links between positive and negative affect situations and problem drinking, few studies have directly addressed whether interventions that target affect regulation positively impact drinking outcomes. This study proposes to conduct a fully-powered Stage II efficacy trial to compare our Affect Regulation Treatment (ART) intervention to an active health and lifestyle control and explore mechanisms of action by which ART exerts its positive effects. If successful, the findings from this study are anticipated to have a direct impat on clinical practice by providing the field with a novel, effective treatment for alcohol use disorders that addresses affect regulation difficulties.